/Engine/Source/Editor/UnrealEd/Public/SComponentClassCombo.h
If the component type is not loaded, this stores data that can be used for class filtering.
[TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [IUnloadedBlueprintData](API\Editor\ClassViewer\IUnloadedBlueprintData) > GetUnloadedBlueprintData() const